Contrast-enhanced ultrasound in developing countriesUp to G-I-N Africa - Discussion Board
Contrast-enhanced ultrasound in developing countriesPosted by Richard Mendelson at April 19. 2016
Most developing countries are unable to afford to purchase or maintain CT and MRI machines, other than perhaps in their major centres. In addition to capital outlay, recurrent costs, maintenance and human resourcing are problematical in these poorer countries. On the other hand, many health facilities outside their major centres do have ultrasound machines. Indeed, in many of these nations, US is the staple imaging modality in addition to plain radiography. For several years an adjunct to conventional ultrasound – Contrast-Enhanced Ultrasound (CEUS) - has been developed and gained widespread acceptance around the world. It provides an excellent safe and relatively cheap alternative to CT and MRI in many clinical scenarios, potentially often obviating the need for transfer of the patient to a major centre, and having the additional advantages of lower cost, safety, and (in middle-level developing countries) usually existing widespread availability of US machines and conventional US expertise.
CEUS can be performed on conventional US machines with dedicated software (based on contrast harmonic imaging/phase inversion techniques) with some additional training of sonographers and imaging specialists. CEUS provides a good alternative to CT and MRI in the examination of many solid organs, especially in the abdomen (liver and kidneys, in particular) and vascular structures. The contrast agent is administered by peripheral intravenous injection. The enhancement patterns of lesions can be studied during multiple vascular phases in a similar fashion to contrast enhanced CT and MRI, but in real time, with resultant higher temporal resolution than is possible with other imaging modalities. Other advantages of CEUS over CT and MRI are that it can be performed immediately, in a variety of scenarios (e.g. in a rural clinic, without need for transfer of the patient) without radiation shielding and at the bedside or in an Emergency Department. In addition, unlike CT and MRI contrast agents, US contrast can be given in the presence of renal impairment without a need for laboratory tests prior to administration.
We believe that CEUS provides a potentially extremely important, cheap and easily disseminated significant part of the solution to the problem of advanced imaging in developing countries.
A group of us from Perth, Western Australia (two radiologists and two sonographers) has recently held a series of workshops in three different centres in Sri Lanka. These consisted of a morning of illustrated lectures on technique and basic physics, and on clinical applications in the liver and in non-hepatic applications. In the afternoons of the workshops, live demonstrations were performed on local volunteer patients with known lesions. The workshops were supported by the Royal Australian and New Zealand College of Radiologists and the Sri Lankan College of Radiologists. Ultrasound machines, technical support and US contrast (Sonazoid) were provided by GE Medical.
About 130 consultant and trainee radiologists attended in total. Although we have not yet received official feedback from the Sri Lankan College, verbal feedback and our impressions of audience reaction has been very positive. We believe that we have engendered considerable enthusiasm for CEUS in Sri Lanka and that local radiologists will pursue the adoption of the technique